Here's a wild thought: Stan Collymore would probably have been a better choice for David Morrissey's character. Morrissey's performance is very one-dimensional. His range of emotions seems to be limited to suppressed rage, suppressed lust and not-so-suppressed superciliousness (and no, dumb looks of bewilderment don't count).
As for the story itself, the plot is devious and Stone plays a great villain, but I feel that things could have been done much better. The movie really seems to drag at some points.
BTW, I couldn't figure out one thing: why does Stone have to bend forward and place her left hand on the small of her back every time she lights a cigarette?